contemporary floor plan by Steven Corley Randel, Architect - general sizing/space requirements for new master bath use as reference. i would switch the tub for a shower and use the old shower space for a bigger linen closet/ bath product storage
Would put another false wall btwn toilet and bath.
Bathtub against the bedroom middle wall, sinks where tub is in picture. Where shower is in picture is where half bath toilet and sink add on would be
2 sinks bathroom with shower and tab